During oceanic flights, crew of an aircraft may wish to adjust the flight level of their aircraft to take advantage of favorable winds that may be found at different altitudes, thereby improving fuel efficiency and/or reducing flight times. For example, if the aircraft is travelling in the direction of the jet stream, it is desirable for the aircraft to fly within the jet stream so as to take advantage of prevailing wind speeds. Conversely, if the aircraft is heading in a direction that opposes prevailing wind speeds, it is desirable to fly at an altitude where the prevailing opposing wind speeds are absent or are minimal.
However, due to aircraft traffic congestion in the various established oceanic flight routes, the crew of the aircraft must be aware of other nearby aircraft before initiating an altitude change so as to avoid a mid-air collision. That is, the crew of the aircraft must know the location, bearing, altitude, and airspeed of nearby aircraft so that when the altitude change is implemented, minimum safe self-separation distances from other nearby aircraft are maintained.
Aircraft are now equipped with automatic dependent surveillance broadcast (ADS-B) equipment, or variations thereof. ADS-B equipment periodically broadcasts information pertaining to the aircraft's current location, bearing, altitude, and/or airspeed. Other information, such as weather condition information, may be included in the ADS-B broadcast. Aircraft receiving the ADS-B information are then able to accurately determine the requisite information about nearby aircraft so that an altitude change may be safely implemented.
An In-Trail procedure (ITP) has been established so that altitude-changing aircraft, referred to as an ITP aircraft, are able to maintain safe-separation distances from other nearby aircraft during an ITP ascent/descent maneuver. An example ITP procedure specifies a minimum safe self-separation distance between aircraft of fifteen nautical miles that are either in front of or behind the ITP aircraft during the ITP maneuver.
When there are multiple nearby aircraft, some of which are travelling in the same direction of the ITP aircraft and others which are travelling in opposite directions to the ITP aircraft, the process of identifying opportunity windows to initiate a compliant ITP maneuver becomes relatively complex. The process of identifying ITP maneuver opportunity windows is further complicated when the multiple nearby aircraft are travelling at different velocities and altitudes.
Accordingly, there is a need in the arts to assist the crew of the ITP aircraft to identify ITP maneuver opportunity windows. Further, when multiple nearby aircraft are present, there is a need in the arts to assist the crew of the ITP aircraft to identify multiple ITP ascent/descent maneuver opportunity windows.